Hydrogen halides with epoxides

In the following procedure, use is made of the basic character of epoxides. In the presence of phosphonium salts, ethylene oxide removes hydrogen halide and the alkylidenetriphenylphosphorane is produced. If a suitable carbonyl compound is present in the reaction mixture, its reaction with the in situ generated phosphorane proceeds readily to give the Wittig product. 

Cleavage of epoxides with hydrogen halides Addition of hypohalous acids to alkenes... 

When simple aliphatic epoxides such as propylene oxide react with hydrogen halides, the dominant product has the halide at the less-substituted primary carbon.111... 

Vinylic sulfides containing an a hydrogen can also be alkylated1516 by alkyl halides or epoxides. In one application, the ion 124, which can be prepared in three steps from epi-chlorohydrin, reacts with alkyl halides to give the bis(methylthio) compound 125,1517 which... 

The polymerizable groups include methacryloyl, styrenic, epoxide, vinyl ether, and others, among which the methacryloyl-capped macromonomers are most widely available from vinyl ethers, styrene, and its derivatives. For example, the a-end methacryloyl group can be introduced by the functional initiator method, with the hydrogen halide-adduct of 2-... 

Epoxides, like other ethers, react with hydrogen halides. In the first step of the reaction, the nucleophilic oxygen is protonated by the acid. The protonated epoxide is then attacked by the halide ion. Because epoxides are so much more reactive than ethers, the reaction takes place readily at room temperature. (Recall that the reaction of an ether with a hydrogen halide requires heat.)... 

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